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Sipwise C5 mr9.3.1 Released

We are excited to announce the general availability of the Sipwise C5CE and C5PRO mr9.3.1 release.

What is the Sipwise C5 platform?

Sipwise C5 PRO Architecture Overview

The Sipwise C5 platform is a highly versatile open source based VoIP soft-switch for ISPs and ITSPs to serve large numbers of SIP subscribers. It leverages existing building blocks like Kamailio, Sems and Asterisk to create a feature-rich and high-performance system by glueing them together in a best-practice approach and implementing missing pieces on top of it. Sipwise engineers have been working with Asterisk and Kamailio (and its predecessors SER and OpenSER) since 2004, and have roles on the management board of Kamailio and are contributing to these projects both in terms of patches and also financially by sponsoring development tasks. The Sipwise C5 platform is available as a Community Edition (CE), which is fully free and open source, and as a commercial PRO appliance shipped turn-key in a high availability setup. The Sipwise C5 provides secure and feature-rich voice and video communication to end customers (voice, video, instant messaging, presence, buddy lists, file transfer, screen sharing, remote desktop control) and connect them to other SIP-, Mobile- or traditional PSTN-networks. It can therefore act as open Skype replacement system, traditional PSTN replacement, Over-The-Top (OTT) platform and also as a Session Border Controller in front of existing VoIP services in order to enable signaling encryption, IPv6 support, fraud- and Denial-of-Service prevention. Another use-case is to act as a Class4 SIP concentrator to bundle multiple SIP peerings for other VoIP services.

What’s new in mr9.3.1?

The most important changes for mr9.3 compared to mr9.2 are:

  • Add support for AEAD-AES-GCM SRTP encryption (RFC 7714, for both SDES and DTLS). [TT#108551]
  • New emergency_location_format, emergency_location_object and emergency_provider_info domain’s preferences. The configuration of those params is described in the dedicated documentation at Emergency Geo-location Formats. [TT#54608]
  • New no_404_fallback subscriber’s preference to deactivate the fallback due to extended matching or e164_to_ruri modes. [TT#62051]
  • Add new method to access the admin voicebox: calling voiceboxpin it will asked you to enter the password/pin but not your extension number [TT#110943]
  • Add kamailio.proxy.rtpengine_bleg config.yml preference. The preference will activate RTPengine on the outgoing leg of the call (b-leg) even for cases where it is not strictly necessary like in no-pbx cases [TT#89560]
  • [Pro/Carrier] Add kamailio.proxy.skip_pbx_loop config.yml preference. It allows to skip the PBX loop for calls from/to subscribers of cloudpbx customers. The preference is at the moment kept disabled because still in experimental stage.
  • [Pro/Carrier] New send_sip_message TPCC command to send aribitrary SIP messages to devices. At the moment only NOTICE and INFO are supported. TPCC module is required. [TT#81003]
  • Change SRTP crypto suites order to prefer stronger crypto suites over weaker ones. [TT#108552]
  • Use SHA-256 DTLS fingerprint by default instead of SHA-1. SHA-1 is still available for use but must be configured explicitly. [TT#108552]
  • The monit service entries for MariaDB have been renamed from mysql and mysql_cluster to mariadb and mariadb-cluster. [TT#108502]
  • [PRO/Carrier] Stop installing PBX firmware by default. The CLI script ngcp-insert-pbx-devices downloads missing firmwares automatically. [TT#97751]
  • [Pro/Carrier] Call features like Parking, Pickup and Music on Hold have been moved from SEMS ngcp_pbx profile to ngcp base profile. [TT#89555]
  • [Pro/Carrier] In cases where PBX subscribers are involved, the second activation of RTPengine has been moved from before SEMS b2b to the outgoing leg of the call (b-leg). This to ensure a better control on the outgoing sdp. [TT#89560]

See the list of all changes in PDF Changelog mr9.3.1

What is mr9.3.1?

The build mr9.3.1 is the last build for release mr9.3, mr9.3.1 provides new features and bugfixes.

Is mr9.3.1 LTS (long time supported) release?

No. See the release calendar on

How do I test-drive the new version?

As usual, we’re providing a VMWare Image, a Virtualbox Image and a Vagrant Box for quick evaluation testing. For those of you using Amazon Cloud we provide the EC2 AMIs in the following regions:

  • AMI ID for region ap-northeast-1: ami-09aa52bff5bb14aca
  • AMI ID for region ap-southeast-1: ami-0b9eb751caa1390dd
  • AMI ID for region ap-southeast-2: ami-041f4a799c39cf0fa
  • AMI ID for region eu-central-1: ami-06da4e1ed2930a2e8
  • AMI ID for region eu-west-1: ami-045b72ae422f6ffa3
  • AMI ID for region sa-east-1: ami-0dfb17850d3f086d9
  • AMI ID for region us-east-1: ami-00396a0602b3882de
  • AMI ID for region us-west-1: ami-0d89c5f0a7b3598fe
  • AMI ID for region us-west-2: ami-0fa90e20bf4f61e10

Check the relevant section in the Sipwise C5 CE Handbook for detailed instructions.

How do I install the new version or upgrade from an older one?

For new users, please follow the Installation Instructions in the Handbook to set up the Sipwise C5 CE mr9.3.1 from scratch. For the users of the previous version of Sipwise C5 CE, please follow the upgrade procedure outlined in the Handbook. If you have customized your configurations using customtt.tt2 files, you must migrate your changes to the new configuration files after the upgrade, otherwise, all your calls will most certainly fail. Hint: modern patchtt.tt2 framework can help you here in the future.

How can I contribute to the project?

Sipwise is publishing software components at Please check it regularly for new projects to appear there, and feel free to fork them and send us pull requests. For development related questions, please subscribe to our Dev Mailing-List at


We want to thank our PRO/Carrier customers and the Sipwise C5 CE community for their feedback, bug reports and feature suggestions to make this release happen. We hope you enjoy using our software and keep your input coming. A big thank you also to all the developers of Kamailio, Sems and Prosody, who make it possible for us to provide an innovative and future-proof SIP/XMPP engine as the core of our platform! And last but not least a HUGE thank you to the Sipwise development team, who worked insanely hard to create this release. You are awesome!